Use ttf2eot for IE7 support - closes endtwist/fontcustom#36

Hi,

First off, thank you SO much for this awesome tool.  Like the other users in endtwist/fontcustom#36, I have had trouble using the `eot` fonts generated with `mkeot` in Internet Explorer 7.  Switching to `ttf2eot` has fixed this issue for me.

Installing `ttf2eot` with `brew install ttf2eot` works great on OS X, but threw errors on Ubuntu 12.04.1 LTS (precise).  Luckily [Issue 22](https://code.google.com/p/ttf2eot/issues/detail?id=22) included a patch that solves this error.  The following code installs a working copy of ttf2eot on Ubuntu.

```bash
curl -O http://ttf2eot.googlecode.com/files/ttf2eot-0.0.2-2.tar.gz && \
    tar --no-same-owner -zxf ttf2eot-0.0.2-2.tar.gz && \
    cd ttf2eot-0.0.2-2 && \
    curl 'http://ttf2eot.googlecode.com/issues/attachment?aid=220001000&name=cstddef.patch&token=UA99q6il-FrbnCsnfkBjWMVa7vk%3A1358417775911' > 22.patch && \
    patch -p1 < 22.patch && \
    make && \
    sudo cp ttf2eot /usr/local/bin/ && \
    cd .. && \
    rm -rf ttf2eot-0.0.2-2 ttf2eot-0.0.2-2.tar.gz
```